Enhancing quantum cryptography with quantum dot single-photon sources

npj Quantum Information, Journal Year: 2022, Volume and Issue: 8(1)

Published: Sept. 8, 2022

Quantum cryptography harnesses quantum light, in particular single photons, to provide security guarantees that cannot be reached by classical means. For each cryptographic task, the feature of interest is directly related photons' non-classical properties. dot-based single-photon sources are remarkable candidates, as they can principle emit deterministically, with high brightness and low multiphoton contribution. Here, we show these additional benefits, thanks tunability coherence emitted photon-number states. We identify optimal optical pumping scheme for main quantum-cryptographic primitives, benchmark their performance respect Poisson-distributed such attenuated laser states down-conversion sources. In particular, elaborate on advantage using phonon-assisted two-photon excitation rather than resonant key distribution other primitives. The presented results will guide future developments solid-state information science photon tailored communication tasks.

Language: Английский

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A quantum key distribution testbed using a plug&play telecom-wavelength single-photon source

Applied Physics Reviews, Journal Year: 2022, Volume and Issue: 9(1)

Published: Jan. 26, 2022

Deterministic solid state quantum light sources are considered key building blocks for future communication networks. While several proof-of-principle experiments of using such have been realized, most them required large setups—often involving liquid helium infrastructure or bulky closed-cycle cryotechnology. In this work, we report on the first distribution (QKD) testbed a compact benchtop dot single-photon source operating at telecom wavelengths. The plug&play device emits pulses O-band wavelengths (1321 nm) and is based directly fiber-pigtailed deterministically fabricated integrated into Stirling cryocooler. housed in 19 in. rack module including all accessories stand-alone operation. Implemented simple QKD emulating BB84 protocol with polarization coding, achieve an multiphoton suppression g(2)(0)=0.10±0.01 raw rate up to (4.72 ± 0.13) kHz external pump laser. setting, further evaluate performance our terms bit error ratios, secure rates, tolerable losses expected full implementations while accounting finite size effects. Furthermore, investigate optimal settings two-dimensional temporal acceptance window applied receiver side, resulting predicted 23.19 dB. Not least, compare results previous proof-of-concept sources. Our study represents important step forward development fiber-based quantum-secured networks exploiting sub-Poissonian

Language: Английский

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Quantum Key Distribution Using a Quantum Emitter in Hexagonal Boron Nitride

Advanced Quantum Technologies, Journal Year: 2023, Volume and Issue: 6(9)

Published: June 22, 2023

Abstract Quantum key distribution (QKD) is considered the most immediate application to be widely implemented among a variety of potential quantum technologies. QKD enables sharing secret keys between distant users by using photons as information carriers. An ongoing endeavor implement these protocols in practice robust, and compact manner so efficiently deployable range real‐world scenarios. Single photon sources (SPS) solid‐state materials are prime candidates this respect. This article demonstrates room temperature, discrete‐variable system bright single source hexagonal‐boron nitride, operating free‐space. Employing an easily interchangeable system, with one million bits length, approximately 70000 bits, at bit error rate 6%, ε‐security 10 −10 generated. study first proof concept finite‐key BB84 realized hBN defects.

Language: Английский

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Single-emitter quantum key distribution over 175 km of fibre with optimised finite key rates

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: June 16, 2023

Quantum key distribution with solid-state single-photon emitters is gaining traction due to their rapidly improving performance and compatibility future quantum networks. Here we emulate a scheme quantum-dot-generated single photons frequency-converted 1550 nm, achieving count rates of 1.6 MHz [Formula: see text] asymptotic positive over 175 km telecom fibre. We show that the commonly used finite-key analysis for non-decoy state QKD drastically overestimates secure acquisition times overly loose bounds on statistical fluctuations. Using tighter multiplicative Chernoff bound constrain estimated finite parameters, reduce required number received signals by factor 108. The resulting rate approaches limit at all achievable distances in one hour, 100 generate keys 13 kbps minute acquisition. This result an important step towards long-distance single-emitter networking.

Language: Английский

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Telecom-band quantum dot technologies for long-distance quantum networks

Nature Nanotechnology, Journal Year: 2023, Volume and Issue: 18(12), P. 1389 - 1400

Published: Dec. 1, 2023

Language: Английский

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Eco-friendly and efficient synthesis of nitrogen-doped carbon quantum dots for pH sensing applications

Applied Physics A, Journal Year: 2024, Volume and Issue: 130(2)

Published: Jan. 23, 2024

Language: Английский

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High-rate intercity quantum key distribution with a semiconductor single-photon source

Light Science & Applications, Journal Year: 2024, Volume and Issue: 13(1)

Published: July 2, 2024

Abstract Quantum key distribution (QKD) enables the transmission of information that is secure against general attacks by eavesdroppers. The use on-demand quantum light sources in QKD protocols expected to help improve security and maximum tolerable loss. Semiconductor dots (QDs) are a promising building block for communication applications because deterministic emission single photons with high brightness low multiphoton contribution. Here we report on first intercity experiment using bright photon source. A BB84 protocol based polarisation encoding realised high-rate telecommunication C-band emitted from semiconductor QD embedded circular Bragg grating structure. Utilising 79 km long link 25.49 dB loss (equivalent 130 direct-connected optical fibre) between German cities Hannover Braunschweig, record-high secret bits per pulse 4.8 × 10 −5 an average bit error ratio ~ 0.65% demonstrated. An asymptotic 28.11 found, corresponding length 144 standard fibre. Deterministic therefore challenge state-of-the-art have potential excel measurement device independent repeater applications.

Language: Английский

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Advances in Chip-Based Quantum Key Distribution

Entropy, Journal Year: 2022, Volume and Issue: 24(10), P. 1334 - 1334

Published: Sept. 22, 2022

Quantum key distribution (QKD), guaranteed by the principles of quantum mechanics, is one most promising solutions for future secure communication. Integrated photonics provides a stable, compact, and robust platform implementation complex photonic circuits amenable to mass manufacture, also allows generation, detection, processing states light at growing system’s scale, functionality, complexity. compelling technology integration QKD systems. In this review, we summarize advances in integrated systems, including photon sources, detectors, encoding decoding components implements. Complete demonstrations various schemes based on chips are discussed.

Language: Английский

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Plug‐and‐Play Single‐Photon Devices with Efficient Fiber‐Quantum Dot Interface

Advanced Quantum Technologies, Journal Year: 2022, Volume and Issue: 5(10)

Published: Aug. 7, 2022

Incorporating solid-state quantum emitters into optical fiber networks enables the long-distance transmission of information and remote connection distributed nodes. However, interfacing with optics encounters several challenges, including low coupling efficiency stability. Here, we demonstrate a highly efficient fiber-interfacing photonic device that directly launches single photons from dots standard FC/PC-connectorized single-mode (SMF28). Optimally designed structures based on hole gratings produce an ultra-narrow directional beam matches small numerical aperture fiber. A pick-and-place technique selectively integrates miniaturized core Our approach realizes plug-and-play single-photon does not require any alignment thus guarantees long-term The results represent major step toward practical reliable lights across network.

Language: Английский

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Quantum Machine Learning for Security Assessment in the Internet of Medical Things (IoMT)

Future Internet, Journal Year: 2023, Volume and Issue: 15(8), P. 271 - 271

Published: Aug. 15, 2023

Internet of Medical Things (IoMT) is an ecosystem composed connected electronic items such as small sensors/actuators and other cyber-physical devices (CPDs) in medical services. When these are linked together, they can support patients through monitoring, analysis, reporting more autonomous intelligent ways. The IoMT devices; however, often do not have sufficient computing resources onboard for service security assurance while the services handle large quantities sensitive private health-related data. This leads to several research problems on how improve systems. paper focuses quantum machine learning assess vulnerabilities provides a comprehensive review both traditional techniques vulnerability assessment. also proposes innovative fused semi-supervised model, which compared state-of-the-art extensive experiment. experiment shows competitive performance proposed model against models highlights usefulness assessments its future applications.

Language: Английский

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